柳塔矿回采巷道破坏特征与支护参数优化

Failure Characteristics and Support Parameter Optimization of Mining Roadway in Liuta Mine

针对柳塔矿322中0401主运巷道受二次采动影响导致巷道严重片帮的问题,采用现场监测、数值模拟等研究方法,对巷道围岩破坏情况、围岩塑性区及应力变化情况进行了研究。结果表明:顶板主要由砂质泥岩及细粒砂岩组成,巷道两帮的松动圈边界在二次采动影响下随着与工作面距离减小而增加,且煤柱帮松动圈范围大于煤壁帮;巷道在工作面前方20~30 m内受采动影响较大,最大主应力达到9 MPa;巷道受二次采动影响下,顶板破坏范围较小,两帮破坏深度达到2.0 m。提出适用于本煤层工作面回采的“锚杆-锚索+网联合支护”的巷道优化支护方案,有效控制了二次采动影响下的巷道围岩变形,保证了回采作业安全进行。

In view of the problem that the 0401 main haulage roadway in middle of 322 of Liuta mine is affected by secondary mining, resulting in serious wall fragmentation, by means of on-site monitoring and numerical simulation, the failure of roadway surrounding rock, plastic zone and stress change under the influence of secondary mining of mining face are studied. The results show that: the roof is mainly composed of sandy mudstone and fine-grained sandstone, after the roadway is affected by secondary mining, the loosening range of the two sides gradually increases with the decrease of the distance from the mining face, and the range of loose circle of coal pillar wall is larger than that of coal wall;the roadway is greatly affected by mining within 20-30 m in front of the mining face, and the maximum principal stress reaches 9 MPa;under the influence of secondary mining, the roof damage range of the roadway is small, and the damage depth of the two sides reaches 2.0 m. An optimized roadway support scheme of "bolt anchor cable+mesh combined support" suitable for roadway mining in this coal seam is proposed, which effectively controls the deformation of roadway surrounding rock under the influence of secondary mining and ensures the safety of mining operation.